Truss structure for upright-piano cases



Patented Apr. 5, 1927.

PATENT OFFICE.

UNITED STATES JAMES D. I-IURST, OF ROCKFORD, ILLINOIS ASSIGNOR TO SCHUMANN PIANO COM- PANY, OF ROCKFORD, ILLINOIS, A CORPORATION OF ILLINOIS.

TRUSS STRUCTURE FOR UPRIGHT-PIANO CASES.

Application filed March 2, 1923.

This invention relates to upright pianos,

and has more particular reference to the case, especially the truss structure beneath the front corners of the key bed.

The general practice heretofore, has been to mount each truss on a rather bulky and heavy toe reaching forwardly from the case beyond the lower end of the truss. Such construction is objectionable, among other reasons, because it necessitated assembly of the toe and truss pieces with the case before finishing,andfurthermore, was inimical to slender and graceful lines in design of the case.

In the present invention, I have aimed primarily to improve the construction of an upright piano case by the provision of a novel truss structure, which promotes econonly in manufacture and harmony with the general lines of a piano of this style.

In furtherance of this general object, I have provided a supporting truss beneath each front corner of the key bed which is directly supported at its lower end, preferably on a caster, and held in rigid relation tothe case by a base-piece.

Another object is to provide a truss unit composed of a truss and stile rigidly joined attheir top and bottom ends by a truss cap and a base piece, this unit being adapted to be manufactured and finished independently of the case and to be easily secured thereto in proper operative relation to the key bed and side and other contiguous parts.

Other objects and attendant advantages will be appreciated by those skilled in this art as the invention becomes better understood by reference to the following description when considered in. connection with the accompanying drawing, in which- Figure 1 is a perspective view showing an upright piano embodying my invention;

Fig. 2 is a sectional view taken substantially on the line 22 of Fig. 1;

Figs. 3 and 4: are detail sections taken on the lines 3-3 and 44, respectively, of Fig. 2;

Fig. 5 is a perspective view of one of the truss units attached to a side of the case;

Fig. 6 is a perspective view of the basepiece used in said'truss unit; and

Fig. 7 is a perspective view, partly broken away, of the lower end of the stile used 1n said unit.

The piano case aside from the truss structhe case.

Serial No. 622,294;

ture beneath the key bed, which forms the subject matter of the present invention, may be of any suitable or preferred construction. In the present illustration, the well known parts shown comprise sides 8, toe rail 9, bottom frame or panel 11, key

bed 12, fall board 13, cheeks 14', combined top frame and music shelf 15 and top 16.

The truss structure beneath the key bed at each end of the piano is of similar construction, consequently, a. description of one will suffice. The primary purpose of this truss structure is to support the key bed and also to carry the forward lean of the piano whenever occasion requires, as for example, when moving the piano or when it 18 supported on an uneven floor, it being evident that ordinarily the greater bulk of the weight is carried on the base proper of According to the present invention, therefore, the truss 1 7 isemployed beneath the forward corner of the key-bed, resting at its lower end on the floor directly through the agency of a caster or the equivalent, 'andproperly fixed at its upper and lower ends to the case. It will thus be seen that the truss serves to support the key-bed and to carry the forward lean of the piano as distinguished from prior constructions in which the heavy forwardly projecting toe structure at the bottom of the case was provided for and relied upon for this purpose] Furthermore, by locating the truss at the extreme forward edge or corner of the keybed I am enabled to employ a slender and comparatively light truss bar which, by reason of its location farther forward from the case than is the usual practice, provides a greater leverage in supporting the forward lean and is for this reason thoroughly practical for a piano of the type disclosed herein. Another advantage of this construction is that it enables the design of a piano case having plain, slender and graceful lines as distinguished from the conventional designs which invariably include a heavy toe structure at the base and pilasters at the sides above the cheeks. It will also be noted that according to my invention each truss reaches from the key-bed, or the equivalent, downwardly to the base line of the piano, whereas in prior constructions the truss seats onto or is attached at its lower end to the top of the toe which reaches forwardly from the base and underlies the truss.

I prefer (but not necessarily) to employ this truss in a unit of assembly which may be manufactured and finished independently of the case proper and applied thereto at the most convenient time in the production.

This unit comprises in the present example the truss 17 referred to, an upright stile 18, a truss cap 19 and a base-piece 21, these reference numerals being generally applied. These parts are rigidly held together in a rectangular structure. In the present instance, the truss cap is secured by dowels 92 and 23 to the truss and stile respectively, and the base-piece 21 has a tenon 20 on its forward end mortised into the truss and tits at its rear end into the rabbeted part 24 of the stile. The joints referred to are glued. The base-piece has a rearward extension 26 adapted to overlap and be secured to the side 8 as by means of screws 27. A filler block 28 applied to the inner end of said extension 26 serves as a reinforcement and also for closing the rear opening of the mortise 29 in the lower end of the stile for the reception of the toe rail 9. The stile 1S and truss cap 19 are secured to the side 8 and key-bed 12 respectively by screws 31 and 32.

It will be manifest from the foregoing that a very rigidly united truss unit is provided which may be manufactured, assembled and finished independently of the case proper and which by reason of its construction may be composed of timber having relatively small cross-sectional area, but possessing ample strength and durability for the functions described above. At the most advantageous time in the manufacture of the piano the truss unit may be attached to the case. This construction enables the use of a fiat board for the side 8 as it is not necessary to apply the usual back truss, toe and other parts to the lower portion of the side when manufacturing the case. Another advantage of this construction is that it lends itself particularly well to slender and graceful lines harmonizing with the major lines of the case.

It is believed that the foregoing conveys a clear understanding of the objects prefaced above, and while I have illustrated but a single working embodiment it should be understood that changes might be made in details of construction without departing from the spirit and scope of the invention as expressed in the appended claims.

I claim: 7

1. In an upright piano, in combination with the case, a truss unit of assembly adapted for attachment to and detachment from the case beneath each end of the key-board comprising a truss proper and an upright stile joined at the top and bottom and held in rigid spaced relation by a truss cap and a base-piece, respectively, the truss proper being equipped at the lower end with a caster and disposed in front of the base piece to support forward lean of the piano, and means for detachably connecting the upright stile of each unit to the inner side of one of the sides of the case and the truss cap to the underside of the key-board.

2. In an upright piano, in combination with a case, a truss unit of assembly for each end of the case comprising a truss proper, an upright stile, a truss cap rigidly joining the upper ends of the stile and truss, a basepiece rigidly joining the lower ends of the stile and truss, the base-piece being mortised into the rear side of the truss, and means for detachably connecting the truss unit to the case beneath the key-board, the truss proper extending down to the base line of the case and equipped at its lower end with a'caster.

JAMES n. HURST. 

